III group nitrides, such as gallium nitride (GaN), aluminum nitride (AlN), and indium gallium nitride (InGaN), are chiefly used in a light-emitting diode (LED) because they have excellent thermal stability and a directly shift energy band structure. Specifically, the III group nitrides are chiefly used in a blue LED and an ultraviolet LED (UV LED).
An UV LED which emits UV rays is packed in a specific body (or case), fabricated, and sold. In this case, the UV rays emitted by the UV LED may discolor or alter other parts including the body of a light emitting module. The discoloration or alteration of the body or other parts attributable to UV rays may have a bad effect on reliability or durability of a light emitting module including an UV LED.